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Evaluating a string as a variable name

Evaluating a string as a variable name

My program will replace some strings in text source files of a scripted program in order to customise the scripts.

Here is a sample of text :

var PROJECT=/*Name_Of_Project*/="Default Project Name";

The sequence "/*Name_Of_Project*/" is a comment which is also acting as my target for string search, which is not the problem.

If the string "Name_Of_Project" is padded up

"/*" & "Name_Of_Project" & "*/"

it will form the string to search for.

But if I also have declared in the VBasic

Public Name_Of_Project As String

QUESTION
How to take a parameter inside my function that has been given the string value
"Name_Of_Project" and make it give me the value of the Public String Variable
Name_Of_Project

For example in JavaScript

var X="Apple";
var Y = "X"

The expression eval(Y) will return the string "Apple".
Is there any equivalent in VBasic?

As I have a number of such strings and variables planned it will make the code more compact if I was able to use such a device.

borov

There is no such thing in VB, but you can easily do it - just write your own collection of parameters (using std collection is not very convinient - you must Remove/Add item to change it value). I have no sources under hand, but it's easy task - just override Item propery and make Set property, too. Using built-in VB5 class builder, its relatively easy task. Than your code will look like:

Dim Vars as new ParamsCollection
.....
Vars("Name_Of_Project") = Variable_Of_Any_Kind
....
INeedIt = Vars("Name_Of_Project")

RM032397

ASKER

I regret to say that I find this answer very unclear.

borov

OK, lets put in some clarity. I meant writing your own COM class implementing a collection of parameters.

Here Is full source code:

VERSION 1.0 CLASS
BEGIN
MultiUse = -1 'True
END
Attribute VB_Name = "ParamCollection"
Attribute VB_GlobalNameSpace = False
Attribute VB_Creatable = True
Attribute VB_PredeclaredId = False
Attribute VB_Exposed = True
Attribute VB_Ext_KEY = "SavedWithClassBuilder" ,"Yes"
Attribute VB_Ext_KEY = "Collection" ,"T"
Attribute VB_Ext_KEY = "Member0" ,"T"
Attribute VB_Ext_KEY = "Top_Level" ,"Yes"
Option Explicit

Private mCol As Collection

Public Sub Add(sKey As String, ByVal vData As String)
mCol.Add vData, sKey
End Sub

Public Property Get Item(vntIndexKey As Variant) As String
Attribute Item.VB_UserMemId = 0
Item = mCol(vntIndexKey)
End Property

Public Property Let Item(vntIndexKey As Variant, ByVal vData As String)
On Error GoTo Item_Error
mCol.Remove vntIndexKey
mCol.Add vData, CStr(vntIndexKey)
Item_Error:
End Property

Public Property Get Count() As Long
Count = mCol.Count
End Property

Public Sub Remove(vntIndexKey As Variant)
mCol.Remove vntIndexKey
End Sub

Public Property Get NewEnum() As IUnknown
Attribute NewEnum.VB_UserMemId = -4
Attribute NewEnum.VB_MemberFlags = "40"
Set NewEnum = mCol.[_NewEnum]
End Property

Private Sub Class_Initialize()
Set mCol = New Collection
End Sub

Private Sub Class_Terminate()
Set mCol = Nothing
End Sub

RM032397

ASKER

Thanks for the code borov. I'll need some time to figure out how this might help me because the fact is it is beyond me at least until I study it in detail.

seahpc: The system is showing an error in giving answer-2 to this question which I assume is your contribution. I cannot respond to your answer except to tell you this, as I cannot see your answer, only that in #1 above it says "Grade seahpc's answer:" !

ASKER CERTIFIED SOLUTION

aikimark

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RM032397

ASKER

Thanks. This is not what I had hoped for but it will have to do.
Thanks to both respondents for their trouble which is appreciated.